Method and apparatus for forming cutting-tools.



W, P. CANNING.

METHOD AND APPARATUS FOR FORMING CUTTING TOOLS.

APPLICATION FILED 'JULY, 1| I916.

Patented May 1, 1917.

2 SHEETSSHEET I.

WITNESSES W. P. CANNING.

METHOD AND APPARATUS FOR FORMING CUTTING TOOLS.

Patented May 1, 1917. 2 SHEETS-SHEET 2 INVENTOR APPLICATION FILED JULY1, 1916.

WQMWM W 1 WW WILLIAM P. CANNING, OF PITTSBURGH, PENNSYLVANIA, ASSIGNORT0 UNITED ENGI- NEERING AND FOUNDRY COMPANY, OF PITTSBURGH,PENNSYLVANIA, A CORPORA- TION OF PENNSYLVANIA.

Specification of Letters Patent.

Patented May 1, 1917.

Application filed July 1, 1916. Serial No. 107,168.

To all whom, it may concern:

Be it known that I, WILLIAM P. CANNING, a citizen of the United States,residing at Pittsburgh, Allegheny county, Pennsylvama, have invented anew and useful Improvement in Methods and Apparatus for FormingCutting-Tools, of which the following is a full, clear, and exactdescription, reference being had to the accompanying drawings, formingpart of this specification, in which Figures 1 and 2 are views partly inelevation and partly in vertical section showing one ,form of apparatusfor carrying out my invention, the two views being taken in planes atsubstantially right angles to each other. I

Fig. 3 is a view in elevation of a portion of a cutter wheel havingtherein tooth cutters formed in accordance with my invention, and

Fig. 4 is a detail view showing a portion of one of the finishedcutters.

My invention has relation to the manufacture of cutting tools, such asmilling cutters, turning and planing tools, and is designed to provide amethod and apparatus by means of which such cutters may be shaped andprovided with the proper backing ofl or clearance simultaneously withthe forming operation and without the necessity for separate operationstherefor.

My invention will be best understood by reference to the accompanyingdrawings, which will now be described, it-being premised, however, thatthe invention is susceptible to various modifications within the scopeof the appended claims.

In these drawings I have shown my inven-.

tion as applied to the making of milling cutters in the form of teethadapted to be inserted in a cutter wheel.

In accordance with my invention I first provide blanks 2 of suitablestock, and place a plurality of these blanks in a rotary carrier 3 whichmay be substantially similar in form to the cutter wheel in which thecutters are to be subsequently used. The sockets of this carrier wheel3, however, instead of being formed in radial relation to the center ofthe wheel are formed non-radially, or tangentially, as shown in Fig. 1.The blanks may be secured in the sockets of the wheel 3 by any suitableclamping means, such as the wedges 4 held by the screws 5. The carrierwheel is then placed on the spindle of an ordinary lathe, as indicatedin Fig. 2. I provide the tool rest or slide 6 of the lathe with a holder7 for a shaping tool 8. This holder 7 is made removable and interchanea-ble, and is provided with a seat 9 for t e tool 8 adapted to holdsaid tool at an oblique angle. The obliquity of this angle is equal tothe obliquity of they angle at which the cutter blanks 2 are held in thecarrier 3 with respect to the radii of said wheel, but the inclinationis in the reverse direction, as will clearly appear from Fig. 1. Thetool 8 is provided with the shaping cavity 10 corresponding to theprofile of the cutter to be formed.

The carrier 3 with the blanks is then rotated in the direction indicatedby the arrow in Fig. 1, the tool slide of the lathe being in themeanwhile gradually fed in. It will be readily seen that as the blanksare shaped they are at the same time out in such a manner that whensubsequently placed radially in a cutter wheel 11 (Fig. 3) they willhave the end clearance 12 and the side clearances 13, without thenecessity for special backing ofl' operations. Before placing the cutterblanks in the carrier 3, they may be roughed down in a lathe to theapproximate size.

By seating the shaping tool 8 at an oblique angle in the mannerdescribed, it will be readily seen that it is unnecessary to provide thecutting edges of this tool with any backing ofl or clearance, and thatit may be iven the exact contour of the cutter to be ormed. However, aspecially shaped tool having proper backing-off and set in a radialposition might be used.

The advantages of my invention will be apparent to those skilled in theart, since it provides an extremely simple method and means of formingmilling and other cutters, and by which any number of cutters of thesame shap:1 can be accurately made with the same bac of inclination ofthe shaping tools, any desired degree of backing ofi' or clearance canbe provided simultaneously with the shaping operation. While myinvention may be carried out on an ordinary lathe, it is obvious that itmay be embodied in special machines for the purpose. The invention isalso susceptible of various other modifications with ng-ofi'. Bychanging the anglerespect to the character of the carrier for theblanks; the holder for the shaping tool, and with respect to the meansfor providing relative cutting and feedin movements between the tooland'the blan s.

I claim: I

1. The herein described method of making a rotary cutter, which consistsin holding a blank with its longitudinal axis oblique to the directionof such axis in a finished tool When in a cutting position, andsubjecting the blank while so held to the action of a forming tool andthen securing the cutting tool thus formed in a rotary cutter carrierwith the longitudinal axis of the cutting tool at a different angle fromthat of the blank during the forming operation, substantially asdescribed.

2. The herein described method of mak ing a rotary cutter, whichconsists in holding a blank having substantially parallel front and rearside edges in a holder in a position in which both its parallel sideedges are in non-radial relation to the axis of, said holder, subjectingthe blank while so held to the action of a forming tool, and thensecuring the tool so formed in a cutter holder in a position in whichone of said parallel edges is in radial relation to the axis of saidholder, substantially as described.

3. The herein described method of making cutting tools, which consistsin setting a suitable blank in a carrier or support in non-radialrelation to the axis of the carrier or support, and inoperative relationto a 'relation to a shapin having means for holdin ing a plurality ofcutter forming blanks in a rotatable carrier in non-radial relation tothe axis of said carrier, and in operative tool held in a reverseoblique osition, an then rotating the carrier to ring the several blanksto the action of said shaping tool, substantially as described.

5. Apparatus for forming cutting tools, comprising a rotatable carrierhaving means for holding a tool blank in non-radlal relation to thecenter thereof, and a tool holder a shaping tool in a reverse obliquepositlon, substantially as described.

6. Apparatus for forming cutting tools, comprising a rotary carrierhaving blank seats therein in non-radial relation to the axis of thecarrier, and a shaping tool holder arranged to support the shaping toolat an oblique angle, said holder and tool being removable andinterchangeable, substantially as described.

7. Ap aratus for forming cutting tools, comprislng a rotatable carrierhaving a plurality of blank seats which are in non-radial relation tothe center of the carrier, means for removably clamping tool blanks insaid seats, a relatlvely fixed shaping tool holder having means forholding the shapin tool in non-radial relation to the axis of saidrotatable carrier and at an inclination which is the reverse of that ofthe blanks, and means for rotating said carrier to bring the blankssuccessively to the action of such tool, substantially as described.

In testimony whereof, I have hereunto set my hand.

WILLIAM P. CANNING.

' Witnesses:-

JOHN J. SWINBANK, GEORGE Vn'rmn, Jr.

